The present invention is directed to electronic labels and display devices. More particularly, the present invention is directed to the tracking of changes in state, changes in location or changes in information related to an item associated with an electronic label.
The use of Radio Frequency Identification (RFID) tags are quickly gaining popularity for use in the monitoring and tracking of an item. RPID technology allows a user to remotely store and retrieve data in connection with an item utilizing a small, unobtrusive tag. As a RFID tag operates in the radio frequency (RF) portion of the electromagnetic spectrum, an electromagnetic or electrostatic coupling can occur between a RPID tag affixed to an item and a RFID tag reader. This coupling is advantageous, as it precludes the need for a direct contact or line of sight connection between the tag and the reader. A RPID tag may additionally incorporate an Electronic Product Code (EPC) number that serves to identify a specific item with a unique code. Additionally, a RFID tag may also include various storage means which allow for the storage of information related to the item to which the tag is affixed. Furthermore, data relating to an item can be stored in one or more databases linked to the RPID tag. These databases do not reside on the tag, but rather are linked to the tag through a unique identifier (5) or reference key (s).
Utilizing a RPID tag, an item may be tagged at a period when the initial properties of the item are known. For example, this first tagging of the item may correspond with the beginning of the manufacturing process, or may occur as an item is first packaged for delivery. Electronically tagging the item allows for subsequent electronic exchanges of information between the tagged item and a user, wherein a user may read information stored within the tag and may additionally write information to the tag. While such an arrangement is beneficial, several notable drawbacks exist.
First, following a communication with a tag, a user has no readily available indication if the communication was successful. In an assembly line setting, for example, it is difficult to determine if each item passing a tag reader is read successfully. Furthermore, should one become aware that at least one item was not read, it is time consuming and difficult to pinpoint which item failed to be read successfully. To ensure inventory accuracy in such a situation it may become necessary to reprocess a large number of items a second time in order to account for the missing item. Additionally, when scanning a number of tagged items that are all in close proximity to each other, it is oftentimes burdensome to determine which item tag a user is actually reading.
RPID tags may be employed in both manual and automatic scanning environments. An example of an automatic scanning environment is a conveyor belt with numerous tagged items passing a tag reader. A manual scanning environment, in contrast, is exhibited by a user utilizing a handheld tag reader to query individual packages within a warehouse. When employed in a manual scanning environment, existing RFID techniques require the user to look at a display external to the tag to view information. The display can be an integral part of a handheld manual reader or may be indirectly connected to the reader using various means such as a corded connection or wireless link. The reader may also take the form of a standalone computer system that displays RPID tag information on a computer monitor. Utilizing such an arrangement, a user is burdened by having to look at a computer screen or paper printout in order to try and understand what is transpiring electronically. In light of this, a user's attention is diverted away from the item. Such a diversion is clearly inefficient and may be potentially dangerous.
Additionally, as RFID technology has been implemented on a large global scale, active and passive RFID tags are being embedded within a high percentage of consumer and commercial items. These tags may be active or passive in nature and may communicate on various wavelengths within the electromagnetic spectrum. Active RPID tags are powered by an internal battery and typically support read from the tag, writing to the tag or a combination of both. Passive RPID tags operate without a separate external power source and generate operating power upon communication with the reader. In comparison to active tags, passive tags are much lighter, less expensive, and offer a virtually unlimited operational lifetime. Passive RFID tags typically only support reading information from the tag.
Both active and passive RFID tag may operate within various regions of the radio frequency spectrum. Low-frequency (30 KHz to 500 KHz) tags have low system costs and are limited to short reading ranges. Low frequency tags are commonly used in security access and animal identification applications. High-frequency (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) tags offer increased read ranges and high reading speeds. One common application of high frequency tags is automated toll collection on highways and interstates.
The long life and continuous operation of RFID tags, coupled with the distances at which a tag may be read, has caused considerable controversy regarding privacy concerns. A purchaser of a tagged item may pay for a product, leave the store, yet the embedded tag remains activate. An active tag can then be continually read from a distance without the knowledge or consent of the purchaser. Additionally, if the tagged item was purchased using a credit card or debit card, it is 15 possible to associate the unique ill of the tag to the identity of the purchaser. An association such as this essentially allows tracking of individuals based upon tagged items that they have purchased.